Optionally Extendable, Runged Tire-Mount Platform Device

ABSTRACT

A ladder-like access device is suited for securing to a tire of a vehicle by means of a strap, rope, chain, cable or similar structure. The device may include extendable legs to adapt its length to a range of wheel and tire sizes. A variety of structures, materials and construction methods are described and claimed.

CONTINUITY AND CLAIM OF PRIORITY

This U.S. patent application claims the benefit of provisionalapplication No. 61/518,229 filed 2-May-2011 and provisional applicationNo. 61/505,275 filed 7-Jul.-2011.

FIELD

The invention relates to access or work platforms that may be removablymounted to a vehicle, to provide improved access to the engine, windowsor roof of such vehicles.

BACKGROUND

The prior art includes several different tire mount platform devices.Examples include those disclosed in U.S. Pat. Nos. 2,575,503; 2,848,150;2,851,312; 2,973,052; 4,947,961; 5,133,429; 6,044,928; and 6,550,578;the disclosures of which are incorporated by reference. Clearly, thegeneral idea of mounting a work or access platform to a vehicle tire isknown.

Problems with prior-art wheel-mounting platform devices, however,include that many offer only a single step or platform, thus limiting orrestricting access (e.g., ascending to the engine compartment/hood area)and usability on different-sized vehicles. In the prior art embodimentsthat include more than one step, only two steps are provided and theyare arranged substantially vertically. It is more difficult to climbvertically-disposed steps than steps mounted diagonally, and verticalsteps offer less flexible access when loading, securing or unloadingcargo from a roof of a vehicle.

Furthermore, when climbing vertically-arranged steps, one may be forcedto use one hand to hold on to the vehicle if the vehicle body bulges outbeyond the tire. A different step orientation may alleviate thisrequirement, freeing both the user's hands to carry tools, supplies, alight, beverage or the like as he mounts the steps.

Another shortcoming of prior art tire mounting steps and/or platforms isthat their height is of limited adjustability. Many such platformssimply hang from the top of the tire, so it may be difficult to steponto the platform when attached to very large tires, and it may bedifficult to raise or lower heavy cargo when there is a tall step.

Yet another disadvantage of prior-art tire-mount platform devices isthat many attach to the top of the wheel and simply dangle clown. If thevehicle does not have the parking brake set and for automatics, thetransmission placed in “park,” then the vehicle may accidentally roll.This results in the step(s) falling off the wheel, with a high chance ofinjury to the user.

An adjustable tire-mount access device that addresses these shortcomingsmay be of significant value in this field.

SUMMARY

Embodiments of the invention provide height-adjustable tire-mountplatforms that offer improved access to upper portions of vehicles, suchas engine compartments, windows, roofs, roof racks, and so on.Embodiments may be particularly useful on pickup trucks, vans, SUVs andservice vehicles.

An extendable tire-mount device in accordance with the present inventionmay include one or more of extendable legs, diagonal positioning whenmounted, a flexible and adjustable mounting harness, and a tire-sideface on the platform that is concave or recessed to better fit the tire.The extendable legs may be rungless, merely extending the legs of therunged section; or may provide additional rungs to facilitate climbing.

BRIEF DESCRIPTION OF DRAWINGS

Embodiments of the invention are illustrated by way of example and notby way of limitation in the figures of the accompanying drawings inwhich like references indicate similar elements. It should be noted thatreferences to “an” or “one” embodiment in this disclosure are notnecessarily to the same embodiment, and such references mean “at leastone.”

FIGS. 1A and 1B show views of an embodiment of the invention incollapsed and extended configurations.

FIGS. 2A and 2B show views of another embodiment of the invention incollapsed and extended configurations.

FIG. 3 shows a third embodiment of the invention.

FIG. 4 shows a simplified structure to explain how the top step of anembodiment may be shaped to fit more securely to a vehicle tire.

FIG. 5 shows a non-extendable embodiment secured to a tire.

FIG. 6 shows another non-extendable embodiment with an alternate methodof securement.

DETAILED DESCRIPTION

Embodiments of the invention are generally similar to, and give thevisual impression of, fixed or extendable stepladders, but all include astructure or component for securing the embodiment to a tire, so that auser can more easily access out-of-reach areas on a taller vehicle forcleaning, repair or storage manipulation.

FIGS. 1A and 1B show two views of a first representative embodiment ofthe invention. In FIG. 1A, the “stepladder” portion of the embodiment iscollapsed: a front portion 100 comprising three steps 105, 110, 115 anda top portion 120; is secured to a rear, extendable portion 130 byside-mounted rail guides 140 and 145. A locking pin 150 is shown near ahole in the frame 155; to lock the extendable portion at a desiredposition, the pin is inserted into the hole (a similar locking pin isprovided on the other side of the embodiment, but it is not visible inthis view). A web 160 is attached at several points to the ladder frame,and a buckle 170 allows adjustment of a portion of the web. The stepsand top portion may be provided with anti-slip features such as the grittape depicted as black stripes on each step.

FIG. 1B shows the same embodiment in an extended configuration: rearportion 130 has been released by withdrawing the locking pins, extendedor slid down, and secured by re-inserting the pins. In this view, theright side rails 101 and 131 of front and rear portions 100 and 130 areidentified. Either or both pairs of side rails may have a protective,anti-slip foot attached, as shown at 102. The web structure identifiedgenerally as 160 in FIG. 1A can be seen to comprise a number of straps162, 164, 166 and 168, which may be sewn, riveted, or woven together, orconnected using buckles or other conventional means. Buckle 170 permitsadjustment of the size of circumferential loop 162.

FIGS. 2A and 2B show another embodiment in collapsed and extendedconfigurations. In this embodiment, a lower portion 200 surrounds anupper extendable portion 240, allowing the upper portion to slide up andclown (as suggested by arrow 250) when the locking mechanism at 280 isdisengaged.

Lower portion 200 comprises side rails 210, 215; rungs 220 and a rearbrace 230. The lower ends of rails 210 and 215 may be capped byanti-scratch, anti-slip feet 212 and 217. Upper portion 240 comprisesside rails (not identified), rungs (one of which is identified as 260),and a top 270. This embodiment has a single securing strap identified as290.

FIG. 3 shows a third extendable embodiment 300, in the extended positiononly. Like the previous embodiments, this one is generally similar to asingle-sided stepladder. The side rails of the upper portion 310 arehollow, square tubes, within which smaller tubes 320, 330 can slide. Toraise or lower upper portion 310, the user can withdraw a locking pinconnected to handle 340, adjust the sliding tube to the desiredposition, and reinsert the locking pin. In this embodiment, the securingweb 350 is made from round, elastic cord (“bungee” or “shock cord”). Thesize and elasticity of the cord may be chosen so that more-complexlocking or adjusting mechanisms are not necessary.

Embodiments of the invention are to be placed against and secured to thetire of a vehicle, to allow the user to climb the ladder safely andreach higher points on the vehicle. For example, an embodiment may besecured to the front tire of a front-engine truck to allow a mechanic toreach the engine bay more easily, or an embodiment may be secured to therear tire of a van to allow the user to reach storage bins or luggageplaced on the top of the vehicle.

FIG. 4 shows a simplified three-dimensional representation of arectangular block 410 (representing the ladder structure of anembodiment) near a toroidal object 420 representing a tire. Block 410and tire 420 have been separated slightly to expose a scalloped area450. The top step of an embodiment of the invention may be formed with asimilar scalloped profile, to improve the stability of the ladder whenit is secured to the tire. The scallop helps keep the ladder fromrocking back and forth against the tire, even if the lower ends areplaced on an uneven or unstable surface.

Although the profile of the scallop is difficult to describe in words,it is easy to compute using standard engineering computer-aided design(“CAD”) tools. Furthermore, since embodiments may be used with a varietyof tire sizes and at differing angles of lean against the tire, theprecise size and shape of the scallop (including top profile 430 andside profile 440) is not critical. An embodiment may comprise scores,protrusions, lugs or the like (indicated generally at 460) to help keepthe top step from sliding from side to side against the tire.

The complex shape of the top step of an embodiment can be manufacturedeasily by molding it of plastic, or with somewhat greater difficulty byforming it from sheet metal or cutting it from another material. In apreferred embodiment, the top step is molded from thermoplastic resin.

The ladder structure of an embodiment may be constructed of anyconventional materials, using any conventional techniques. For example,side rails of the upper and/or lower parts may be made from fiberglasschannels, aluminum channels, wood or another material. Rungs and bracesmay be fiberglass, metal or wood. Side rails and rungs may be joined byscrews, rivets, glue, welding, or other techniques. Protective feet atthe bottom of side rails may be plastic, rubber, or metal.Extension-locking mechanisms may be shear pins, as discussed above, orcompression/friction fittings, ratchets or other structures.

An embodiment may sized to fit a range of tires, but generally, thewidth of an embodiment is preferably within about ±20% of the diameterof the applicable tire, and the length such that the embodiment can beleaned against the tire at an angle from about 45° to about 80° from thehorizontal. (This implies a ladder length from slightly longer than thetire diameter to almost 1.5 times the tire diameter. Of course, anextendable embodiment may be suitable for use with a wider range of tiresizes.) Narrower ladders may provide inferior access for the user, whilevehicle fenders or wheel wells may interfere with wider ladders. Veryshort ladders are not much use, whereas overly long ladders may beinconvenient to transport, or may be more difficult to secure to thetire.

FIG. 5 shows a non-extendable embodiment 500 secured to a tire 410 usinga multi-strap web, with a circumferential strap 520, a coronal strap530, and an auxiliary positioning strap 540. (This embodiment comprisesat least one more auxiliary positioning strap, but it is not visible inthis view.) An embodiment may use buckles, friction fittings, or otherrope/cord/strap-length adjustment mechanisms to set the securing-websize appropriately for the tire to which the embodiment is secured.

The strap or web to secure an embodiment to a tire may be made of nylonwebbing, rope, chain, metal cable, elastic bands or cords, orcombinations of such materials. It is preferred that the main horizontalsecurement strap pass around the tire above the horizontal centerline ofthe wheel (to avoid the axle, brake mechanisms, etc.) and below about75% of the diameter of the tire. If the horizontal strap is too high, itmay tend to slide further up to the top of the tire, thus impairing thesecure attachment. However, it is appreciated that tire-tread features(e.g., side traction lugs) may help keep the strap in place. Other partsof the securing web (e.g., coronal and auxiliary positioning straps) maybe placed to provide easy access to length adjusters and/or suit singleor double-tire wheels. In some embodiments, the securing web may beconstructed of fabric in a half-wheel-cover configuration. The loweredge of such a half wheel cover is similar in positioning and purpose tothe main horizontal strap of other embodiments.

FIG. 6 shows another view of a non-extendable embodiment 600 which usesa single strap 620 to secure it to tire 610. Strap 620 may have a lengthadjustment mechanism (not shown), but for final attachment, the bottomend of the embodiment may simply be pulled away from the tire as shownby arrow 630. This will tighten strap 620 and lever the top of theembodiment against the top of the tire at 640. In this Figure, thescalloped shape of the top of the embodiment and its relationship withthe top of the tire are clearly visible.

Several specific embodiments of the present invention have beendescribed with reference to corresponding Figures. However, those ofskill in the art will recognize that changes in materials andconfigurations may be made without departing from the general principlesof the invention. Such changes and alternate implementations areunderstood to be captured according to the following claims.

1. An access platform to be attached to a tire of a vehicle, theplatform comprising: two upright members spaced apart by a distancewithin 20% of a diameter of a tire; a plurality of horizontal membersjoining the two upright members, the horizontal members spacedvertically by approximately equal distances; a top horizontal memberjoining upper ends of the two upright members, the top horizontal memberhaving a scalloped indentation on at least one side, said scallopedindentation shaped for resting against a side of the tire; and at leastone securing strap attached at each end to one of the two uprightmembers, the at least one securing strap suitable for holding the tophorizontal member against the side of the tire.
 2. The access platformof claim 1 wherein the plurality of horizontal members is threehorizontal members.
 3. The access platform of claim 1 wherein the atleast one securing strap is two securing straps joined by a buckle, saidbuckle allowing adjustment of a length of the securing straps.
 4. Theaccess platform of claim 1 wherein the at least one securing strapcomprises a horizontal securing strap, a coronal strap, and a pluralityof auxiliary positioning straps.
 5. The access platform of claim 1wherein the at least one securing strap is located so as to pass aroundthe tire above a horizontal centerline of the tire and below about 75%of a height of the tire.
 6. An extendable, single-sided stepladder to beattached to a tire of a vehicle, comprising: a first ladder framecomprising a plurality of steps and a top platform; a second ladderframe slidably adjustable relative to the first ladder frame, the firstand second ladder frames thus forming a ladder whose length can bechanged; a locking mechanism for fixing the first ladder frame to thesecond ladder frame at a predetermined length; and means for securingthe first ladder frame to a tire of a vehicle.
 7. The extendable,single-sided stepladder of claim 6 wherein the top platform has ascallop formed in at least one side, said scallop suited for securelyresting the top platform against a top of the tire and preventingrocking of the platform against the tire.
 8. The extendable,single-sided stepladder of claim 6 wherein the top platform has asurface feature to prevent the top platform from sliding sidewaysagainst a sidewall of the tire.
 9. The extendable, single-sidedstepladder of claim 8 wherein the surface feature is one of a groove, aridge, or a lug.
 10. The extendable, single-sided stepladder of claim 6wherein the top platform is molded from a plastic material.
 11. Theextendable, single-sided stepladder of claim 6 wherein the lockingmechanism comprises a shear pin inserted through holes in the firstladder frame and the second ladder frame.
 12. The extendable,single-sided stepladder of claim 6 wherein the means for securing thefirst ladder frame to the tire of the vehicle comprises: a horizontalstrap.
 13. The extendable, single-sided stepladder of claim 12 whereinthe horizontal strap is to pass from one side of the first ladder frame,around the tire above a horizontal centerline of the tire and belowabout 75% of a height of the tire, and to another side of the firstladder frame.
 14. The extendable, single-sided stepladder of claim 12wherein the horizontal strap comprises a mechanism for adjusting alength of the horizontal strap.
 15. The extendable, single-sidedstepladder of claim 6 wherein the means for securing the first ladderframe to the tire of the vehicle comprises: a horizontal strap, acoronal strap and at least one auxiliary positioning strap.
 16. Theextendable, single-sided stepladder of claim 6 wherein the means forsecuring the first ladder frame to the tire of the vehicle comprises: atleast one elastic cord.
 17. The extendable, single-sided stepladder ofclaim 6 wherein the means for securing the first ladder frame to thetire of the vehicle comprises at least one of a nylon strap, a chain, ametal cable, a rope or an elastic band.
 18. A secured step platform tobe attached to a tire of a vehicle, the platform comprising: a ladderstructure including two vertical uprights and three horizontal steps;anti-slip feet at lower ends of the two vertical uprights; a top stepextending horizontally from a top of one vertical upright to a top ofanother vertical upright, said top step having an indentation formed onat least one side, said indentation suitable for resting against asidewall of a tire; and a securing structure including at least alength-adjustable member to extend from one vertical upright, around thetire and to the other vertical upright.
 19. The secured step platform ofclaim 18 wherein both of the two vertical uprights are formed fromfiberglass C-channel, aluminum C-channel, fiberglass rectangular tube,aluminum rectangular tube, or wood.
 20. The secured step platform ofclaim 18 wherein all of the three horizontal steps are formed ofaluminum, fiberglass or wood.